Re: [PATCH v4 1/2] wifi: ath11k: use union for vaddr and iaddr in target_mem_chunk

Miaoqing Pan <quic_miaoqing@xxxxxxxxxxx> · Wed, 31 Jul 2024 09:14:43 +0800

On 7/31/2024 1:42 AM, Jeff Johnson wrote:
On 7/29/2024 8:59 PM, Miaoqing Pan wrote:
The value of 'ab->hw_params.fixed_mem_region' determins that

s/determins/determines/

only one variable 'vaddr' or 'iaddr' is used in target_mem_chunk.
So use union instead, easy to check whether the memory is set
or not.

Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-04358-QCAHSPSWPL_V1_V2_SILICONZ_LITE-1

Signed-off-by: Miaoqing Pan <quic_miaoqing@xxxxxxxxxxx>
---
  drivers/net/wireless/ath/ath11k/qmi.c | 45 ++++++++++++++-------------
  drivers/net/wireless/ath/ath11k/qmi.h |  8 +++--
  2 files changed, 29 insertions(+), 24 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/qmi.c b/drivers/net/wireless/ath/ath11k/qmi.c
index 1bc648920ab6..ee32027badcf 100644
--- a/drivers/net/wireless/ath/ath11k/qmi.c
+++ b/drivers/net/wireless/ath/ath11k/qmi.c
@@ -1955,19 +1955,21 @@ static void ath11k_qmi_free_target_mem_chunk(struct ath11k_base *ab)
  	int i;
  
  	for (i = 0; i < ab->qmi.mem_seg_count; i++) {
-		if ((ab->hw_params.fixed_mem_region ||
-		     test_bit(ATH11K_FLAG_FIXED_MEM_RGN, &ab->dev_flags)) &&
-		     ab->qmi.target_mem[i].iaddr)
-			iounmap(ab->qmi.target_mem[i].iaddr);
+		if (!ab->qmi.target_mem[i].v.iaddr)

see my comment at the end about potentially adding a new member to test for NULL

+			continue;
  
-		if (!ab->qmi.target_mem[i].vaddr)
+		if (ab->hw_params.fixed_mem_region ||
+		    test_bit(ATH11K_FLAG_FIXED_MEM_RGN, &ab->dev_flags)) {
+			iounmap(ab->qmi.target_mem[i].v.iaddr);
+			ab->qmi.target_mem[i].v.iaddr = NULL;
  			continue;
+		}
  
  		dma_free_coherent(ab->dev,
  				  ab->qmi.target_mem[i].prev_size,
-				  ab->qmi.target_mem[i].vaddr,
+				  ab->qmi.target_mem[i].v.vaddr,
  				  ab->qmi.target_mem[i].paddr);
-		ab->qmi.target_mem[i].vaddr = NULL;
+		ab->qmi.target_mem[i].v.vaddr = NULL;
  	}
  }
  
@@ -1984,22 +1986,22 @@ static int ath11k_qmi_alloc_target_mem_chunk(struct ath11k_base *ab)
  		/* Firmware reloads in coldboot/firmware recovery.
  		 * in such case, no need to allocate memory for FW again.
  		 */
-		if (chunk->vaddr) {
+		if (chunk->v.vaddr) {
  			if (chunk->prev_type == chunk->type &&
  			    chunk->prev_size == chunk->size)
  				continue;
  
  			/* cannot reuse the existing chunk */
  			dma_free_coherent(ab->dev, chunk->prev_size,
-					  chunk->vaddr, chunk->paddr);
-			chunk->vaddr = NULL;
+					  chunk->v.vaddr, chunk->paddr);
+			chunk->v.vaddr = NULL;
  		}
  
-		chunk->vaddr = dma_alloc_coherent(ab->dev,
-						  chunk->size,
-						  &chunk->paddr,
-						  GFP_KERNEL | __GFP_NOWARN);
-		if (!chunk->vaddr) {
+		chunk->v.vaddr = dma_alloc_coherent(ab->dev,
+						    chunk->size,
+						    &chunk->paddr,
+						    GFP_KERNEL | __GFP_NOWARN);
+		if (!chunk->v.vaddr) {
  			if (ab->qmi.mem_seg_count <= ATH11K_QMI_FW_MEM_REQ_SEGMENT_CNT) {
  				ath11k_dbg(ab, ATH11K_DBG_QMI,
  					   "dma allocation failed (%d B type %u), will try later with small size\n",
@@ -2055,10 +2057,10 @@ static int ath11k_qmi_assign_target_mem_chunk(struct ath11k_base *ab)
  			}
  
  			ab->qmi.target_mem[idx].paddr = res.start;
-			ab->qmi.target_mem[idx].iaddr =
+			ab->qmi.target_mem[idx].v.iaddr =
  				ioremap(ab->qmi.target_mem[idx].paddr,
  					ab->qmi.target_mem[i].size);
-			if (!ab->qmi.target_mem[idx].iaddr)
+			if (!ab->qmi.target_mem[idx].v.iaddr)
  				return -EIO;
  
  			ab->qmi.target_mem[idx].size = ab->qmi.target_mem[i].size;
@@ -2068,7 +2070,7 @@ static int ath11k_qmi_assign_target_mem_chunk(struct ath11k_base *ab)
  			break;
  		case BDF_MEM_REGION_TYPE:
  			ab->qmi.target_mem[idx].paddr = ab->hw_params.bdf_addr;
-			ab->qmi.target_mem[idx].vaddr = NULL;
+			ab->qmi.target_mem[idx].v.iaddr = NULL;
  			ab->qmi.target_mem[idx].size = ab->qmi.target_mem[i].size;
  			ab->qmi.target_mem[idx].type = ab->qmi.target_mem[i].type;
  			idx++;
@@ -2083,18 +2085,19 @@ static int ath11k_qmi_assign_target_mem_chunk(struct ath11k_base *ab)
  				if (hremote_node) {
  					ab->qmi.target_mem[idx].paddr =
  							res.start + host_ddr_sz;
-					ab->qmi.target_mem[idx].iaddr =
+					ab->qmi.target_mem[idx].v.iaddr =
  						ioremap(ab->qmi.target_mem[idx].paddr,
  							ab->qmi.target_mem[i].size);
-					if (!ab->qmi.target_mem[idx].iaddr)
+					if (!ab->qmi.target_mem[idx].v.iaddr)
  						return -EIO;
  				} else {
  					ab->qmi.target_mem[idx].paddr =
  						ATH11K_QMI_CALDB_ADDRESS;
+					ab->qmi.target_mem[idx].v.iaddr = NULL;
  				}
  			} else {
  				ab->qmi.target_mem[idx].paddr = 0;
-				ab->qmi.target_mem[idx].vaddr = NULL;
+				ab->qmi.target_mem[idx].v.iaddr = NULL;
  			}
  			ab->qmi.target_mem[idx].size = ab->qmi.target_mem[i].size;
  			ab->qmi.target_mem[idx].type = ab->qmi.target_mem[i].type;
diff --git a/drivers/net/wireless/ath/ath11k/qmi.h b/drivers/net/wireless/ath/ath11k/qmi.h
index 7e06d100af57..63c957a7075e 100644
--- a/drivers/net/wireless/ath/ath11k/qmi.h
+++ b/drivers/net/wireless/ath/ath11k/qmi.h
@@ -1,7 +1,7 @@
  /* SPDX-License-Identifier: BSD-3-Clause-Clear */
  /*
   * Copyright (c) 2018-2019 The Linux Foundation. All rights reserved.
- * Copyright (c) 2021-2023 Qualcomm Innovation Center, Inc. All rights reserved.
+ * Copyright (c) 2021-2024 Qualcomm Innovation Center, Inc. All rights reserved.
   */
  
  #ifndef ATH11K_QMI_H
@@ -102,8 +102,10 @@ struct target_mem_chunk {
  	u32 prev_size;
  	u32 prev_type;
  	dma_addr_t paddr;
-	u32 *vaddr;
-	void __iomem *iaddr;
+	union {
+		u32 *vaddr;
+		void __iomem *iaddr;
+	} v;

is there a reason you didn't incorporate my prior observation:

...if you make it an anonymous union then most, if not all, of the
code changes are unnecessary.

I'm also thinking it may make the code even cleaner to add a third member to
the union:
	void *anyaddr

So you set and clear either vaddr or iaddr based upon the usage, but test
anyaddr when testing for NULL

Actually, I want ath11k to be the same as ath12k. Anyway, it's a good 
suggestion, will update.







